arGEN-X, a biopharmaceutical company focused on the discovery and development of human monoclonal antibodies from its proprietary SIMPLE Antibody™ platform, announces it has signed a non-exclusive license agreement with BioWa Inc., the exclusive worldwide licensor of POTELLIGENT®Technology.

arGEN-X's SIMPLE Antibody™ platform is unique in providing human variable regions of unprecedented diversity, allowing the rapid selection of antibodies with superb functional potency. In under two years, these attributes have already been validated preclinically in seven in vivo and ex vivo models, highlighting the productivity of the technology.

POTELLIGENT® Technology is a clinically validated approach to producing monoclonal antibodies (mAbs) with significantly enhanced antibody-dependent cellular cytotoxicity (ADCC) and tumor cell killing activity. By combining the power of the SIMPLE Antibody™ platform with POTELLIGENT® Technology, arGEN-X expects to increase the intrinsic potency of these mAbs even further. Under this license agreement, arGEN-X will apply POTELLIGENT® Technology to its own novel mAbs addressing cancer and inflammatory disorders and will offer antibodies encompassing both technologies to its commercial partners.

Dr. Yasunori Yamaguchi, President and CEO of BioWa, commented further: "We are pleased to have this arrangement with an innovative company such as arGEN-X. The SIMPLE Antibody™ platform and POTELLIGENT® Technology are very complementary and promise to enable important increases in therapeutic antibody potency."

arGEN-X aspires to be a transforming force in the therapeutic monoclonal antibody arena. Its SIMPLE Antibody™ platform is unmatched in its ability to blanket human disease targets with functional antibodies, including targets that cannot be accessed by conventional discovery platforms. SIMPLE Antibodies™ have human sequences and structures, femtomolar affinities and potencies as well as excellent manufacturability. The characteristics of SIMPLE Antibodies™ provide arGEN-X and its partners with unprecedented choice in developing differentiated therapeutic mAb products.

arGEN-X™ and SIMPLE Antibody™ are deposited trademarks of arGEN-X BV. SIMPLE stands for Superior Immunodiversity with Minimal Protein Lead Engineering

About POTELLIGENT®Technology

POTELLIGENT® Technology improves potency and efficacy of antibody therapeutics by enhancing ADCC, one of the major mechanisms of action for antibody therapeutics. POTELLIGENT® Technology involves the reduction of the amount of fucose in the carbohydrate structure of an antibody using a proprietary fucosyl transferase-knockout CHO cell line as a production cell. Research shows that POTELLIGENT® Technology dramatically enhances ADCC activity of an antibody in vitro, and significantly increases potency and efficacy of the antibody in vivo. A number of POTELLIGENT® antibodies are being investigated in human clinical trials. Earlier this year, Kyowa Hakko Kirin submitted a New Drug Application in Japan for KW-0761, a POTELLIGENT® antibody for the treatment of Adult T-cell Leukemia-Lymphoma (ATL).

About BioWa

BioWa is a wholly owned subsidiary of Kyowa Hakko Kirin Co., Ltd., Japan's leading pharmaceutical and largest biotech company, and is the exclusive worldwide licensor of the AccretaMab® platform. The AccretaMab® platform consists of POTELLIGENT® and COMPLEGENT® Technologies, creating a superior antibody molecule with enhanced ADCC and CDC activities. BioWa is offering POTELLIGENT® and COMPLEGENT® Technologies to partners under a license to maximize the value of these technologies. Together with Kyowa Hakko Kirin, BioWa is committed to promote ADCC/CDC enhanced monoclonal antibody-based therapeutics to fight cancer and other life-threatening and debilitating diseases. For more information about BioWa, visit its web site at http://www.biowa.com.

POTELLIGENT®, COMPLEGENT®, and AccretaMab® are the trademarks of Kyowa Hakko Kirin Co., Ltd. All rights are reserved.